Phentermine And Topiramate


Qsymia is an extended-release combination of two existing medications: phentermine, used to suppress the appetite to aid in weight loss, and topiramate, used primarily to treat epilepsy and prevent migraine headaches but with a common side effect of weight loss. Qsymia has no generic alternative available. Another prescription option for weight loss, Belviq, is also now available. Compare sympathomimetic / anti-epileptic combinations.

Availability: Qsymia is only available at select pharmacies and through the Qsymia Home Delivery program. Learn More

Insurance Coverage: Many major insurance plans no longer cover Qsymia starting in 2016. Learn More


Phentermine And Topiramate Side Effects

What should I watch for?

Visit your doctor or health care professional for regular checks on your progress. This medicine is intended to be used in addition to a healthy diet and appropriate exercise. The best results are achieved this way. Do not increase or in any way change your dose without consulting your doctor or health care professional.

Do not take this medicine within 6 hours of bedtime. It can keep you from getting to sleep. Avoid drinks that contain caffeine and try to stick to a regular bedtime every night.

Do not stop taking this medicine suddenly. This increases the risk of seizures.

This medicine can decrease sweating and increase your body temperature. Watch for signs of deceased sweating or fever. Avoid extreme heat, hot baths, and saunas. Be careful about exercising, especially in hot weather. Contact your health care provider right away if you notice a fever or decrease in sweating.

You should drink plenty of fluids while taking this medicine. If you have had kidney stones in the past, this will help to reduce your chances of forming kidney stones.

If you have stomach pain, with nausea or vomiting and yellowing of your eyes or skin, call your doctor immediately.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may increase dizziness and drowsiness. Avoid alcoholic drinks.

This medicine may affect blood sugar levels. If you have diabetes, check with your doctor or health care professional before you change your diet or the dose of your diabetic medicine.

Patients and their families should watch out for worsening depression or thoughts of suicide. Also watch out for sudden changes in feelings such as feeling anxious, agitated, panicky, irritable, hostile, aggressive, impulsive, severely restless, overly excited and hyperactive, or not being able to sleep. If this happens, especially at the beginning of treatment or after a change in dose, call your health care professional.

If you notice blurred vision, eye pain, or other eye problems, seek medical attention at once for an eye exam.

This medicine may increase the chance of developing metabolic acidosis. If left untreated, this can cause kidney stones, bone disease, or slowed growth in children. Symptoms include breathing fast, fatigue, loss of appetite, irregular heartbeat, or loss of consciousness. Call your doctor immediately if you experience any of these side effects. Also, tell your doctor about any surgery you plan on having while taking this medicine since this may increase your risk for metabolic acidosis.

Women who become pregnant while using this medicine should contact their physician immediately. You should also contact The Qsymia Pregnancy Surveillance Program which is a program that monitors pregnancies that occur during treatment. Contact the program by calling 1-888-998-4887.


Interactions with Medications

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

Chest discomfort


decreased urine

fast, irregular, pounding, or racing heartbeat or pulse

loss of appetite

mood changes

muscle pain or cramps

nausea or vomiting

numbness or tingling in the hands, feet, or lips

shortness of breath

unusual tiredness or weakness


Blood in the urine

pain in the groin or genitals

sharp back pain just below the ribs

Incidence not known

Blistering, peeling, or loosening of the skin

blisters on the mouth, trunk, scalp, or other areas

blurred or decreased vision

chest pain

chills or shivering


continuing nausea or vomiting

cough or sore throat

dark urine

diarrhea or light-colored stools



increase in the frequency of seizures

irregular heartbeat


joint or muscle pain

loss of appetite

low body temperature

muscle aches or weakness

pain in the shoulders, arms, jaw, or neck

red skin lesions, often with a purple center

red, irritated eyes

shakiness in the legs, arms, hands, or feet

sores, ulcers, or white spots in the mouth or on the lips


swelling of the face

tiredness and weakness

trouble thinking, speaking, or walking

upper right abdominal or stomach pain

weak or feeble pulse

weight gain

yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Back pain

change in taste

difficulty having a bowel movement (stool)

ear congestion

fear or nervousness

loss of taste

loss of voice

memory problems

pain or tenderness around the eyes and cheekbones


stuffy or runny nose

trouble sleeping

Less common



decreased appetite

dry eyes

eye pain

hair loss

heartburn or indigestion

heavy bleeding



stomach discomfort, upset, or pain

Incidence not known


false or unusual sense of well-being

feeling that others are watching you or controlling your behavior

feeling that others can hear your thoughts

feeling, seeing, or hearing things that are not there

hives or welts

change in sexual ability, desire, drive, or performance

severe mood or mental changes

unusual behavior

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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